Hypopituitarism is a rare disorder in which your pituitary gland either fails to produce one or more of its hormones or doesn't produce enough of them.

The pituitary is a small bean-shaped gland situated at the base of your brain, behind your nose and between your ears. Despite its size, this gland secretes hormones that influence nearly every part of your body.

In hypopituitarism, you have a short supply of one or more of these pituitary hormones. This deficiency can affect any number of your body's routine functions, such as growth, blood pressure and reproduction.

You'll likely need medications for the rest of your life to treat hypopituitarism, but your symptoms can be controlled.

Hypopituitarism is often progressive. Although the signs and symptoms can occur suddenly, they more often develop gradually. They are sometimes subtle and may be overlooked for months or even years.

Signs and symptoms of hypopituitarism vary, depending on which pituitary hormones are deficient and how severe the deficiency is. They may include:

Fatigue

Weight loss

Decreased sex drive

Sensitivity to cold or difficulty staying warm

Decreased appetite

Facial puffiness

Anemia

Infertility

Hot flashes, irregular or no periods, loss of pubic hair, and inability to produce milk for breast-feeding in women

Decreased facial or body hair in men

Short stature in children

When to see a doctor

See your doctor if you develop signs and symptoms associated with hypopituitarism.

Hypopituitarism may be the result of inherited disorders, but more often it's acquired. Hypopituitarism frequently is triggered by a tumor of the pituitary gland. As a pituitary tumor increases in size, it can compress and damage pituitary tissue, interfering with hormone production. A tumor can also compress the optic nerves, causing visual disturbances.

The cause of hypopituitarism can also be other diseases and events that damage the pituitary, such as:

Head injuries

Brain or pituitary tumors

Brain surgery

Radiation treatment

Autoimmune inflammation (hypophysitis)

Stroke

Infections of the brain, such as meningitis

Tuberculosis

Infiltrative diseases, such as sarcoidosis, which is an inflammatory disease occurring in various organs; histiocytosis X, in which abnormal cells cause scarring in numerous parts of the body, such as the lungs and bones; and hemochromatosis, which causes excess iron deposition in the liver and other tissues

Severe loss of blood during childbirth, which may cause damage to the front part of the pituitary gland (Sheehan syndrome or postpartum pituitary necrosis)

Genetic mutations resulting in impaired pituitary hormone production

Diseases of the hypothalamus, a portion of the brain situated just above the pituitary, also can cause hypopituitarism. The hypothalamus produces hormones of its own that directly affect the activity of the pituitary.

In some cases, the cause of hypopituitarism is unknown.

You're likely to start by seeing your family doctor or a general practitioner. However, in some cases, when you call to set up an appointment, you may be referred to a specialist called an endocrinologist.

Here's some information to help you prepare for your appointment.

What you can do

Be aware of any pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do to prepare for common diagnostic tests.

Write down all symptoms and changes you're experiencing, even if they seem unrelated to each other.

Write down key personal information, including any recent life changes or a noticeable difference in your ability to tolerate stress.

Make a list of your key medical information, including recent surgical procedures, the names of all medications you're taking and any other conditions for which you've been treated. Your doctor will also want to know about any recent injuries to your head.

Take a family member or friend along, if possible. Someone who accompanies you may help you remember what your doctor tells you.

Write down questions to ask your doctor.

Create a list of questions before your appointment so that you can make the most of your time with your doctor. For hypopituitarism, some basic questions to ask your doctor include:

What is likely causing my symptoms or condition?

Other than the most likely cause, what are other possible causes for my symptoms or condition?

What tests do I need?

Is my condition likely temporary or chronic?

What treatment approach do you recommend?

How long will I need to take medications?

How will you monitor whether my treatment is working?

I have other health conditions. How can I best manage them together?

Are there restrictions I need to follow?

Is there a generic alternative to the medicine you're prescribing?

Do you have brochures or other printed material I can take with me? What websites do you recommend?

Don't hesitate to ask any questions you have during your appointment.

What to expect from your doctor

Your doctor is likely to ask you some questions, such as:

What are your symptoms, and when did you first notice them?

How have your symptoms changed over time?

Have you noticed any changes in your vision?

Do you experience severe headaches?

Has your appearance changed, including your weight or the amount of your body hair?

Have you lost interest in sex? Has your menstrual cycle changed?

Are you currently being treated or have you recently been treated for any other medical conditions?

Have you recently had a baby?

Have you had a recent head injury or neurosurgery?

Have any of your family members been diagnosed with pituitary or hormonal conditions?

What, if anything, seems to improve your symptoms?

What, if anything, appears to worsen your symptoms?

If your doctor suspects a pituitary disorder, he or she will likely order several tests to check levels of various hormones in your body. Your doctor may also want to check for hypopituitarism if you've had a recent head injury or radiation treatment that might have put you at risk of damage to your pituitary gland.

Tests your doctor may order include:

Blood tests. They can help detect deficits in hormones as a result of pituitary failure. For example, blood tests can identify low levels of thyroid, adrenal or sex hormones, and can determine if these low levels are associated with inadequate pituitary hormone production.

Stimulation or dynamic testing. Your doctor may suggest you go to a specialized endocrine clinic for these tests, which check your body's secretion of hormones after you've taken certain medications that can stimulate hormone production.

Vision tests. These tests can determine if growth of a pituitary tumor has impaired your sight or visual fields.

Successful treatment of the underlying condition causing hypopituitarism may lead to a complete or partial recovery of your body's normal production of pituitary hormones. Treatment with the appropriate hormones is often the first line of treatment. These drugs are considered as "replacement," rather than treatment, because the dosages are set to match the amounts that your body would normally manufacture if it didn't have a pituitary problem. Treatment may be lifelong.

Treatment for pituitary tumors may involve surgery to remove the growth. In some instances, doctors also recommend radiation treatment.

Hormone replacement medications may include:

Corticosteroids. These drugs, such as hydrocortisone or prednisone, replace the adrenal hormones that aren't being produced because of an adrenocorticotropic hormone (ACTH) deficiency. You take them by mouth.

Sex hormones. These include testosterone in men and estrogen or a combination of estrogen and progesterone in women. Testosterone is administered through the skin with either a patch or a gel or by injection. Female hormone replacement can be administered with pills, gels or patches.

Growth hormone. Also called somatropin, growth hormone is taken through an injection beneath your skin. It promotes growth, thus producing more normal height in children. Adults with a growth hormone deficiency also may benefit from growth hormone replacement, but they won't grow taller.

If you've become infertile, LH and FSH( gonadotropins) can be administered by injection to stimulate ovulation in women and sperm production in men.

Monitoring and adjusting

A doctor who specializes in endocrine disorders (endocrinologist) may monitor the levels of these hormones in your blood to ensure you're getting adequate — but not excessive — amounts.

Your doctor will advise you to adjust your dosage of corticosteroids if you become seriously ill or experience major physical stress. During these times, your body would ordinarily produce extra cortisol hormone. The same kind of fine-tuning of dosage may be necessary when you have the flu, experience diarrhea or vomiting, or have surgery or dental procedures. Adjustments in dosage may also be necessary during pregnancy or with marked changes in weight. You may need periodic CT or MRI scans as well to monitor a pituitary tumor or other diseases causing the hypopituitarism.

In case of emergency

Wear a medical alert bracelet or pendant, and carry a special card, notifying others — in emergency situations, for example — that you're taking corticosteroids and other medications.

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